Seasonal Summary for the Canadian Arctic Waters - Summer 2011

Western and Central Arctic

May 2011

Mean air temperatures were above normal values over most locations except near normal over the area from Queen Maud Gulf to Peel Sound (see Table 3). A light to moderate northerly flow prevailed over the Central Arctic, while a light to moderate southeasterly flow developed over the rest of the Western Arctic. At the end of the winter season, consolidated first-year ice was present over the Central Arctic including the Amundsen Gulf area. However concentrations of old ice were much lower than normal over these same areas. A large area of consolidated first-year ice was present along the coast over the southern Beaufort Sea and the Alaskan Coast. During the first two weeks of May, the ice started to fracture over the western section of Amundsen Gulf and drifted westward into the Beaufort Sea. Between the mainland coast and south of 71°30’N, an area of first-year ice with up to 2 tenths of old ice dominated over the region. After mid-May, wide areas of open water started to form over the southeastern Beaufort Sea, west of Banks Island and southwestern Amundsen Gulf. North of 71°30’N, an area of old and first-year ice persisted east of 141°W over the northern Beaufort Sea and the Arctic Ocean, while first-year ice with much lower than normal old ice concentrations dominated west of 141°W. M’Clure Strait was showing signs that the consolidated ice over the western section was fracturing at the end of May. Mid-May ice conditions, as well as the departure from median ice concentrations, are shown in Figure 24 and Figure 25, respectively .

June 2011

Mean air temperatures were near normal values for most locations except above normal near Mould Bay (see Table 3). However, below normal temperatures were observed over Coronation Gulf during the same time period. A light easterly flow developed over the Central Arctic, while a light to moderate southeasterly flow persisted over the rest of the Western Arctic. During the first half of June, little change was observed in the ice conditions except for areas of open water over the southeastern Beaufort Sea and open drift ice over western Amundsen Gulf. West of Point Barrow, a lead of open water developed along the coast off the consolidated first-year ice. For the rest of the month, areas of open water widened over the Beaufort Sea and west of Point Barrow, while the ice fractured over eastern Amundsen Gulf. The ice melted completely during the last week of June over Mackenzie Bay and Kugmallit Bay. With southeasterly winds developing west of Amundsen Gulf, this helped to clear the ice off the Alaskan Coast as far west as Barter Island. A few areas of open drift first-year ice were still present north of Tuktoyaktuk Peninsula and in western M’Clure Strait from the fracture of the consolidated ice. North of 71°30’N, an area of old and first-year ice persisted east of 141°W over the northern Beaufort Sea and the Arctic Ocean, while first-year ice with much lower than normal old ice concentrations dominated west of 141°W. The ice remained consolidated over the Central Arctic with less than normal old ice concentrations. Mid-June ice conditions, as well as the departure from median ice concentrations, are shown in Figure 26 and Figure 27, respectively.

July 2011

Mean air temperatures were above normal values over the whole Western Arctic (see Table 3). At the beginning of July, the ice decay started to accelerate over the area. A light to moderate east to southeasterly flow persisted over the Western Arctic. The ice started to fracture along the southern and northern routes of the Northwest Passage during the first two weeks of July. The consolidated ice north of Tuktoyaktuk Peninsula completely fractured during the first week of July. The persistent southeasterly flow over the Beaufort Sea helped to push the ice westward to a narrow area of first-year ice north of Point Barrow at mid-July. Meanwhile, areas of open water continued to widen rapidly over the southern Beaufort, west of Banks Island and west of Point Barrow. However, isolated areas of open drift first-year ice were still present along the coastal areas from Tuktoyaktuk Peninsula to Barter Island and in Amundsen Gulf. The ice melted completely over southwestern Coronation Gulf and in Bathurst Inlet. The ice remained consolidated over most of M’Clintock Channel and the Queen Elizabeth Islands. In the second half of the month, the ice melted rapidly over most locations across the Western Arctic. Consolidated old ice still persisted over Hazen Strait and Prince Gustaf Adolf Sea. At the end of July, an open water route developed along parts of the Northwest Passage from Amundsen Gulf to Coronation Gulf. An area of open water was present within 90 miles of the shore over the southern Beaufort Sea and along the Alaskan Coast, but isolated patches of first-year ice still remained near Herschel Island and north of Harrison Bay. Most of western M’Clure Strait was clear of ice. First-year ice was still present along the shipping routes from northern Queen Maud Gulf to Peel Sound, in M’Clintock Channel and from Viscount Melville Sound to eastern M’Clure Strait. Large areas of old ice persisted in central Viscount Melville Sound northwest of Stefansson Island and in southwestern M’Clintock Channel. Ice concentrations decreased rapidly over southern Queen Maud Gulf and Rasmussen Basin after mid-month, as very open drift first-year ice dominated over these areas. During the month, an area of old and first-year ice persisted north of 72°N and east of 143°W to 30 miles west of Banks Island, while first-year ice with up to 2 tenths of old ice prevailed west of 143°W. Concentrations of old ice were less than normal over much of the Western Arcticfor the month of July. Mid-July ice conditions, as well as the departure from median ice concentrations, are shown in Figure 28 and Figure 29, respectively.

August 2011

Mean air temperatures remained above normal values over the whole Western Arctic (see Table 3). Just like the Eastern Arctic, rapid ice decay was observed over all areas during the month. During the first week of August, the ice melted completely over northern Queen Maud Gulf and in Rasmussen Basin creating an open water route from central Amundsen Gulf to Taloyoak. Patches of first-year ice persisted near Herschel Island and north of Harrison Bay during the first half of the month. As well, the rapid ice decay and persistent east to southeasterly winds over the Central Arctic helped to melt the ice along the rest of the Northwest Passage from Victoria Strait to Peel Sound and in eastern M’Clintock Channel. However ice concentrations only started to decrease over Viscount Melville Sound during the second week of August, while some of the ice continued to drift westward into eastern M’Clure Strait. So, by mid-August, most shipping routes through the southern route of the Northwest Passage and the Beaufort Sea were clear of ice. Light to moderate east to southeasterly winds which developed over the Central Arctic for the rest of the month helped to compact the ice over western M’Clintock Channel. Meanwhile, as the pack ice continued to drift westward, clearing was occurring over the southern and eastern sections of Viscount Melville Sound. Some of the ice from Viscount Melville Sound drifted across northern M’Clure Strait. Ice free conditions were observed along the shipping route over the Beaufort Sea south of 72°N, the southern section of the Northwest Passage, within 60 miles west of Banks Island and in southern M’Clure Strait. Open drift old and first-year ice dominated over the Beaufort Sea between 72°N and 75°N. At the end of the month, an area of old ice prevailed over the Arctic Ocean north of 75°N and east of 138°W, while first-year ice with up to 2 tenths of old ice persisted west of 138°W. Concentration of old ice was still much less than normal over most of the Western Arctic for the month of August, but was greater than normal over northern Viscount Melville Sound and southwestern M’Clintock Channel. The ice coverage for the end of August set a new record for the Western Arctic as the lowest minimum ice coverage ever recorded since 1968. Mid-August ice conditions, as well as the departure from median ice concentrations, are shown in Figure 30 and Figure 31, respectively.

September 2011

Mean air temperatures remained above normal values over the whole Western Arctic (see Table 3). The remaining ice continued to melt over Parry Channel northward during the first two weeks of September and until the end of September further south. Ice free conditions persisted over the southern Beaufort Sea, along the Alaskan Coast, the southern route of the Northwest Passage, in southern Parry Channel and eastern Viscount Melville Sound during the month. An east to southeasterly flow dominated over the whole Western Arctic except for a short period of northwesterly winds at mid-month which pushed the remaining ice southward over the Central Arctic. During the first two weeks of September, very open drift old ice persisted over Parry Channel west of Byam Martin Channel, north of Stefansson Island and northwestern M’Clintock Channel, while the ice remained compacted along the shore over southwestern M’Clintock Channel. Over the northern Beaufort Sea between 72°N and 74°N, open drift old and first-year ice dominated over the area, while little change in the ice conditions was observed further north. During the last two weeks of September, most of the remaining old ice melted completely over Viscount Melville Sound and in northern M’Clintock Channel. However an area of compacted old ice persisted over southwestern M’Clintock Channel with some of the ice drifting southward into northwestern Victoria Strait. As well, concentration of old ice over Byam Martin Channel started to increase during the second half of the month. The ice coverage for early September set a new record for the Western Arctic as the lowest minimum ice coverage ever recorded since 1968 (see Figure 23). At the end of September, new with some grey ice was forming over the High Arctic and Parry Channel west of Stefansson Island. At that time, grey ice was forming between old ice floes over the Arctic Ocean. Mid-September ice conditions, as well as the departure from median ice concentrations, are shown in Figure 32 and Figure 33, respectively.

Figure 23: Minimum Ice Coverage for the Western Arctic on September 03, 2011. [data]

Table 3: 2011 Temperatures and departures from normal (°C) for the Western Arctic

Stations

May

June

July

August

September

Temp

Depart

Temp

Depart

Temp

Depart

Temp

Depart

Temp

Depart

Mould Bay

-9.2

1.7

1.3

1.3

8.6

4.7

5.0

4.2

-2.5

3.9

Gjoa Haven

-9.9

-0.8

1.8

0.3

10.5

3.0

9.1

3.5

1.5

1.8

Cambridge Bay

-9.3

-0.2

1.1

-1.1

10.9

2.8

9.8

3.6

1.7

2.3

Kuglukt uk

-3.1

1.9

3.7

-1.2

12.5

2.1

11.4

2.8

5.1

2.5

Tuktoyaktuk

-1.3

2.9

6.2

0.0

13.0

2.0

10.6

1.5

4.5

1.8

Point Barrow

-5.1

1.5

1.8

0.1

5.8

1.1

5.7

2.0

2.9

3.3

Figure 24: Western Arctic Regional chart for May 16, 2011.

Figure 25: Departure from normal ice concentration on May 16, 2011 for the Western Arctic.

Figure 26: Western Arctic Regional chart for June 13, 2011.

Figure 27: Departure from normal ice concentration on June 13, 2011 for the Western Arctic.

Figure 28: Western Arctic Regional chart for July 18, 2011.

Figure 29: Departure from normal ice concentration on July 18, 2011 for the Western Arctic.

Figure 30: Western Arctic Regional chart for August 15, 2011.

Figure 31: Departure from normal ice concentration for the Western Arctic on August 15, 2011.

Figure 32: Western Arctic Regional chart for September 12, 2011.

Figure 33: Departure from normal ice concentration for the Western Arctic on September 12, 2011.